Do not touch or handle sick birds.The likely cause is type-E botulism poisoning caused by ingesting a neurotoxin produced by the bacterium Clostridium botulinum. Eating affected birds or fish on beaches could transmit the toxin. Call the appropriate coordinator (below) for safe and legal handling and disposal of birds. If absolutely necessary to handle, be mindful of risks and use common sense health measures: wear gloves, don't touch eyes or mouth, and place carcass in a double-bagged container. Avoid standing downwind of any carcass that you handle. Wash hands and equipment after handling. West Nile Virus, Salmonella, Newcastle Disease, or other transmittable diseases may be present and can be transmitted to human by touch. All can cause serious illness. Keep pets on a leash and away from carcasses.
Policy and Management
Sick Birds. National Park Service policy is to let nature take its course under most circumstances. We do not rescue or euthanize injured or sick birds. Sick birds on beaches have a risk of disease transmission and a limited likelihood for recovery. It is illegal for visitors to handle or remove injured or sick birds.
Dead Birds. On beaches within the park, the Avian Botulism Monitoring crew (NPS staff and volunteers) remove and/or bury dead birds to prevent further spread of disease to wildlife scavengers or to nearby piping plovers, a federally endangered bird. Some bird carcasses are sent to a lab for testing. All birds are documented as part of an on-going Avian Botulism research project. Please do not remove dead birds from the beach.
Avian Botulism. Periodic outbreaks of type-E botulism have occurred in the Great Lakes since the 1960’s, but have become more common and widespread in recent years. While spores of E. botulinum are naturally and widely distributed in the environment, toxin production occurs only when suitable environmental conditions allow spore germination and cell growth. The toxin is a neurotoxin, which causes paralysis and is usually fatal. The locations where toxin is produced in lakes and the mechanisms by which it is transferred through food webs to birds in the Great Lakes remain undefined. However, it is thought that the invasion of dreissenid mussels (Dreissena spp.) has created favorable conditions for the accelerated growth of native Cladophora (the green algae often seen on beaches). As water warms and algae decay in thick mats on the bottom, anaerobic conditions develop and the bacteria begins producing profuse amounts of the toxin. The toxin is then ingested by the invasive round goby and other fish that feed on plankton. Birds get sick by eating these contaminated fish or by scavenging dead birds containing the toxin.
Management. Park staff and volunteers are constantly monitoring beaches for sick or dead birds. With funding through the Great Lakes Restoration Initiative, the NPS and research partners are analyzing data collected on beaches and at several sites located within Lake Michigan. This research effort is ongoing and being used to improve our understanding of toxin transmission through the food web to birds, to develop predictive models of future outbreaks, and to identify management actions that could reduce future avian mortality events.